Format
The format of a citation often defines where the information may be found.
The ideal is to find an exact verification. Sometimes you have to make do with less, or use secondary sources as stepping stones to the complete information.
Book
Author(s). Book Title. City of publication: Publisher; Year. Total Number of Pages.
Ohlsen, Merle M.; Horne, Arthur M.; Lowe, Charles F. Group Counseling. New York : Holt, Rinehart, and Winston; 1988. 416 p.
Book Chapter or Part
Chapter authors. Chapter Title. IN: Book Editors. Book Title. Edition. Place of Publication: Publisher, Date of Publication. Inclusive pagination.
Anderson, Robert J.; Schrier, Robert W. Acute renal failure. IN: Braunswald, Eugene; Isselbacher, Kurt j: Petersdorf, Robert G., etal. Editors. Harrison 's prinicples of internal medicine. 11th ed. New York : McGraw-Hill; 1987. p. 1149-55
Journal Article
Authors. Article Title. Abbreviated Journal Title Year Month (if available); volume(issue): inclusive pages.
Hebert Jr, Barone J. On the possibile relationship between AIDS and nutrition. Med Hypotheses 1988 Sep; 27(1):51-4.
Meeting Abstract
Authors. Title of Paper; Paper Presented at: Name of Conference; Date of Conference, Place of Conference.
Papoulas, O.; Kingston , Robert E. Analysis of c-myc binding to enhancer motifs. Paper presented at: 6th Annual Meeting on Oncogenes; 1990 Jun 26-30; Frederick MD.
Not infrequently, a meeting abstract or poster will be published as a supplement or part of a printed journal. Then it would look similar to the Journal Article, with perhaps a notation of meeting abstract, or A added to the page number. More recently, the meeting abstract may initially only be available through the Conference website. In that case, adding the URL to the site and date last visited should be added in lieu of page number.
Tips and Thoughts
Gather all of the information that is available - if you only need 3 authors for the citation, but all are listed - list them all, with Inclusive paging. You can always remove information, and it is much easier than going back to find more.